High Pressure and High Temperature Vapor Catheters and Systems

ABSTRACT

Devices and systems are described for treating intraluminal locations such as in a patient&#39;s lung. The device has an elongated shaft with an inner lumen, preferably defined by an inner tubular member, formed of heat resistant polymeric materials such as polyimide. The device also has an outer surface formed of heat resistant material. High temperature vapor is directed through the inner lumen into the intraluminal location to treat tissue at and distal to the location. An enlarged or enlargeable member, such as a balloon, is provided on a distal portion of the shaft to prevent proximal flow of the high temperature vapor upon discharge from the device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 11/598,383, filed Nov. 13, 2006; which application is related toapplication Ser. No. 11/598,362, filed Nov. 13, 2006, both of which areincorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to medical devices, systems and methods, and inparticular to intrabronchial catheters, systems and methods fordelivering a high pressure, high temperature vapor to one or more tissuetargets in a patient's lungs.

BACKGROUND OF THE INVENTION

Heating therapies are increasingly used in various medical disciplinesincluding cardiology, dermatology, orthopedics, oncology as well as anumber of other medical specialties. In general, the manifold clinicaleffects of superphysiological tissue temperatures results fromunderlying molecular and cellular responses, including expression ofheat-shock proteins, cell death, protein denaturation, tissuecoagulation and ablation. Associated with these heat-induced cellularalternations and responses are dramatic changes in tissue structure,function and properties that can be exploited for a desired therapeuticoutcome such as tissue injury, shrinkage, modification, destructionand/or removal.

Heating techniques in the lung pose several technical challenges becauselung tissue is more aerated than most tissues and also due to itsvascularization. Accordingly, these new heating methods, devices andsystems for rapid, controllable, effective and efficient heating of lungtissue are needed. The present invention is directed at meeting these aswell as other needs.

SUMMARY OF THE INVENTION

The present invention is generally directed to devices, such ascatheters, and systems for thermally treating a body lumen. The devicehas an inner lumen defined at least in part by a heat resistant materialwhich facilitates delivery of high temperature vapor within a bodylumen. The device may have an enlarged or enlargeable member on a distalportion of the device to prevent proximal flow of high temperature vaporwhich can damage healthy tissue. The device has an exterior which isalso formed of a heat resistant material.

More specifically, the invention relates to novel intrabronchial devicesor catheters, methods and systems for volumetric heating one or moretarget tissues in a patient's lungs. Preferably, the one or more targetlung tissues are heated to superphysiological temperatures (temperaturesabove at least 40 degrees Celsius) by dispersing a vapor in an airwaythat ventilates the one or more target tissues. Because of thephysiological characteristics of the airways, the vapor can be deliveredfocally or regionally dependent on where in the airways the vapor isdispersed.

In a first aspect of the invention, a catheter for treating a patient'slung comprises, an elongated shaft having an inner tubular member formedof heat resistant polymeric material and an outer tubular formed of heatresistant polymeric material disposed about the inner tubular member anddefining at least in part a lumen between the inner and outer tubularmember; an inflatable member on a distal portion of the elongated shaftformed of heat resistant polymeric material having an interior which isin fluid communication with the lumen between the inner and outertubular members. An adapter is located on a proximal portion of theelongated shaft having a first arm. Said adapter is in fluidcommunication with the inner lumen of the inner tubular member and isconfigured to be connected to a heat generator. The adapter may alsohave a second arm which is in fluid communication with the lumen betweenthe inner and outer tubular member and which is configured to beconnected to a source of inflation fluid.

In a preferred embodiment, the inner tubular member and outer tubularmember are preferably formed from a polyimide, preferably a braidedpolyimide polymeric material. The elongated shaft has an outertransverse dimension less than 5 French and the inflatable member isformed of a silicone or a polysilicone. When the inflatable member isinflated, inflatable member preferably has an inflated diameter betweenabout 0.5 to about 2 mm.

In yet another aspect of the invention, a system for treating apatient's lung, comprises: an elongated shaft having an inner tubularmember formed of heat resistant polymeric material with an inner lumenand an outer tubular formed of heat resistant polymeric materialdisposed about the inner tubular member and defining at least in part alumen between the inner and outer tubular member; and an inflatablemember on a distal portion of the elongated shaft formed of heatresistant polymeric material having an interior which is in fluidcommunication with the lumen between the inner and outer tubularmembers; a fluid heating member which is in fluid communication with theinner lumen of the inner tubular member of the elongated catheter andwhich is configured to heat liquid to form a high temperature vapor; andan adapter on the proximal end of the elongated catheter configured tobe in fluid communication with the inner lumen of the inner tubularmember and the fluid heating member.

In yet another aspect of the invention, a medical kit for vapor heatingof one or more target lung tissues comprises a packaged, sterile liquidor liquid composition and a high temperature vapor delivery device orcatheter. Other embodiments of medical kits comprise instructions ofuse, syringes, and the like.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 illustrates a human respiratory system;

FIG. 2 illustrates the airway in the respiratory system;

FIG. 3 illustrates one method of treating a volume of lung tissueembodying features of the present invention;

FIG. 4 is a schematic illustrating an embodiment of a vapor generator inaccordance with the present invention;

FIG. 5 illustrates one embodiment of a generator display or userinterface;

FIG. 6 is a perspective view of an energy delivery catheter embodyingfeatures of the present invention;

FIG. 7 is a longitudinal cross-sectional view of yet another embodimentof a catheter embodying features of the present invention;

FIG. 7A is a transverse cross-sectional view of the catheter of FIG. 7taken along lines 7A-7A; and

FIG. 7B is a transverse cross-sectional view of the catheter illustratedin FIG. 7 taken along lines 7B-7B.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a human respiratory system 10. The respiratory system10 resides within the thorax 12 that occupies a space defined by thechest wall 14 and the diaphragm 16. The human respiratory system 10includes left lung lobes 44 and 46 and right lung lobes 48, 50, and 52.

The respiratory system 10 further includes trachea 18; left and rightmain stem bronchus 20 and 22 (primary, or first generation) and lobarbronchial branches 24, 26, 28, 30, and 32 (second generation). Segmentaland subsegmental branches further bifurcate off the lobar bronchialbranches (third and fourth generation). Each bronchial branch andsub-branch communicates with a different portion of a lung lobe, eitherthe entire lung lobe or a portion thereof. As used herein, the term “airpassageway” or “airway” means a bronchial branch of any generation,including the bronchioles and terminal bronchioles.

FIG. 2 is a perspective view of the airway anatomy emphasizing the upperright lung lobe 48. In addition to the bronchial branches illustrated inFIG. 1, FIG. 2 shows subsegmental bronchial branches (fourth generation)that provide air circulation (i.e. ventilation) to superior right lunglobe 48. The bronchial segments branch into six generations and thebronchioles branch into approximately another three to eight generationsor orders. Each airway generation has a smaller diameter than itspredecessor, with the inside diameter of a generation varying dependingon the particular bronchial branch, and further varying betweenindividuals. A typical lobar bronchus providing air circulation to theupper right upper lobe 48 has an internal diameter of approximately 1cm. Typical segmental bronchi have internal diameter of approximately ofabout 4 to about 7 mm.

The airways of the lungs branch much like the roots of a tree andanatomically constitute an extensive network of air flow conduits thatreach all lung areas and tissues. The airways have extensive branchingthat distally communicates with the parenchyma alveoli where gasexchange occurs. Because of these physiological characteristics of theairways, a medium, such as a vapor, delivered through an airway can bedelivered focally or more regionally dependant on the airway location atwhich the medium is delivered or dispersed.

While not illustrated, a clear, thin, shiny covering, known as theserous coat or pleura, covers the lungs. The inner, visceral layer ofthe pleura is attached to the lungs and the outer parietal layer isattached to the chest wall 14. Both layers are held in place by a filmof pleural fluid in a manner similar to two glass microscope slides thatare wet and stuck together. Essentially, the pleural membrane aroundeach lung forms a continuous sac that encloses the lung and also forms alining for the thoracic cavity 12. The space between the pleuralmembranes forming the lining of the thoracic cavity 12 and the pleuralmembranes enclosing the lungs is referred to as the pleural cavity. Ifthe air tight seal around the lungs created by the pleural members arebreached (via a puncture, tear, or is otherwise damaged) air can enterthe sac and cause the lungs to collapse.

FIG. 3 illustrates generally a procedure in accordance with the presentinvention. FIG. 3 shows a bronchoscope 100 having a working channel intowhich an energy delivery catheter 200 is inserted. Bronchoscope 100 isinserted into a patient's lungs while the proximal portion of the energydelivery catheter 200 remaining outside of the patient. Energy deliverycatheter 200 is adapted to operatively couple to an energy generator 300as further discussed below.

Though not illustrated, patients can be intubated with a double-lumenendobronchial tube during the procedure, which allows for selectiveventilation or deflation of the right and left lung. Depending on thelocation or locations of the target lung tissues to be treated, it maybe preferable to stop ventilation of the target lung tissue. Also, whilenot illustrated, in an alternative embodiment, the procedure can beperformed minimally invasively with energy catheter 200 introducedpercutaneously through the chest wall and advanced to an appropriatelocation for with the aid of an introducer or guide sheath (with orwithout introduction into an airway).

FIG. 4 is a schematic diagram of one embodiment of the present inventionwherein energy generator 300 is configured as a vapor generator.Preferably, vapor generator is configured to deliver a controlled doseof vapor to one or more target lung tissues. Generally, vapor generator300 is adapted to convert a biocompatible liquid 301 (e.g. saline,sterile water or other biocompatible liquid), into a wet or dry vapor,which is then delivered to one or more target tissues. A wet vaporrefers to a vapor that contains vaporous forms of the liquid as well asa non-negligible proportion of minute liquid droplets carried over withand held in suspension in the vapor. A dry vapor refers to a vaporcontained little or no liquid droplets. In general, vapor generator 300is configured to have a liquid capacity between about 1000 to 2500 ccand configured to generate a vapor having a pressure between about 5-100psig and temperatures between about 100-175° C.

Vapor generator 300 is preferably configured as a self-contained,medical-grade generator unit comprising at least a controller (notshown), a vaporizing unit 302, a vapor inlet 304, a vapor outlet 306 anda connective handle (not shown). The vaporizing unit 302 comprises afluid chamber for containing a fluid 302, preferably a biocompatible,sterile fluid, in a liquid state. Vapor outlet 304 is coupled to one ormore pipes or tubes 310, which in turn are in fluid communication with avapor lumen of a hub assembly or other adapter, which in turn is adaptedto operatively couple to the proximal end of energy delivery catheter200. Several embodiments of energy delivery catheter 200 are describedbelow. Vapor flow from vapor generator 300 to a catheter (andspecifically a vapor lumen of said catheter) is depicted as a vapor flowcircuit 314 wherein flow of the vapor in circuit 314 is indicated byarrows 314 in FIG. 4. In a preferred embodiment, vapor generator isconfigured to deliver a reportable dose of vapor energy deliverycatheter 200.

Vaporizer unit 302 is configured to heat and vaporize a liquid containedin a fluid chamber (not shown). Other components can be incorporatedinto the biocompatible liquid 301 or mixed into the vapor. For example,these components can be used in order to control perioperative and/orpost procedural pain, enhance tissue fibrosis, and/or control infection.Other constituents, for the purpose of regulating vapor temperatures andthus control extent and speed of tissue heating, can be incorporated;for example, in one implementation, carbon dioxide, helium, other noblegases can be mixed with the vapor to decrease vapor temperatures.

Vaporizing unit 302 comprises a fluid inlet 304 that is provided toallow liquid 301 to be added to the fluid chamber as needed. Fluidchamber can be configured to accommodate or vaporize sufficient liquidas need to apply vapor to one or more target tissues. Liquid invaporizing unit 302 is heated and vaporized and the vapor flows intovapor outlet 304. A number of hollow thermally conductive pipes 314 areadapted to fluidly connect vapor outlet 304 and connective handle, whichin turn is adapted to operatively couple to a variety of energy deliverycatheters via a hub assembly or other connecting means. Preferably, hubassembly or other connecting means is configured to allow for secure yetquick connect and release from the connective handle of the generator.Preferably, there is little or no vapor-to-liquid transition duringmovement of the vapor through vapor flow circuit 314. Vapor flow throughvapor flow circuit 314 is unidirectional (in the direction of arrows314), accordingly one or more isolation valves 320 are incorporated invapor flow circuit 314. Isolation valves 320, which are normally openduring use of generator 300 to minimize vapor flow in a directionopposite that of the vapor flow circuit 314.

A priming line 330, branching from main vapor flow circuit 314, isprovided to minimize or prevent undesirable liquid-state water formationduring vapor flow through vapor flow circuit 314. Pressure andtemperature changes along vapor flow circuit 314 can affect whether thevapor is sustainable in a vapor state or condensed back into a liquid.Priming line 330 is provided to equalize temperatures and/or pressuresalong vapor flow circuit 314 in order to minimize or prevent undesirableliquid-state transition of the vapor during its progression throughvapor flow circuit 314. In one embodiment, an initial “purge” or“priming” procedure can be preformed prior to delivery of a therapeuticvapor dose in order to preheat flow, circuit 314 thus maintaining aconstant temperature and pressure in the main vapor flow circuit 314prior to delivery of a vapor to the target lung tissue.

As shown in FIG. 4, priming line 330 terminates at evaporator 332, whichis adapted to either house undesirable liquid in a collection unit (notshown) located within generator 300. In one embodiment, collection unitis adapted to house the liquid until a user or clinician is able toempty said collection unit. Alternatively, evaporator 332 is configuredto evaporate and expel said undesirable liquid into the ambient air.Baffle plates (not shown) or other like means can be incorporated inevaporator 332 to facilitate maximal vapor-to-liquid transition. Itshould be understood that other suitable evaporator configurations couldbe included to facilitate vapor-to-liquid transition during a primingprocedure of lines 314.

A number of sensors, operatively connected to a controller, can beincorporated into vapor generator 300, for example, in the liquidchamber, or along any point in vapor flow circuit 314, a number ofsensors can be provided. Water level sensors, adapted to monitor thewater level in the liquid chamber, can be included. These water levelsensors are configured as upper and lower security sensors to sense orindicate when a liquid level in the fluid chamber is below or above aset fluid level. In example, if a water level in the fluid chamber fallsbelow the level of a lower water control sensor, the controller can beconfigured to interrupt the operation of the vapor generator 300.

In yet another embodiment, pressure sensors, or manometers, can beincluded in vaporizing unit 302, or at various points along the vaporflow circuit 314, to measure the liquid or vapor pressures at variousdiscrete locations and/or to measure vapor pressures within a definedsegment along circuit 314. One or more control valves 320 can also beinstalled at various points in the vapor flow circuit 314 to controlvapor flow for instance to control or increase the vapor flow or vaporflow rates in vapor flow circuit 314. In yet another embodiment, asafety valve 322 can be incorporated into the liquid chamber ofvaporizing unit 302 and coupled to a vapor overflow line 340 if the needfor removing or venting vaporizing unit 302 arises during generator 300operation.

FIG. 5 illustrates one embodiment of a user interface 360 of vaporgenerator 300. As illustrated, the user interface 360 comprises variousvisual readouts intended to provide clinical users information aboutvarious treatment parameters of interest, such as pressure, temperatureand/or duration of vapor delivery. Vapor generator 300 can also beadapted to incorporate one or more auditory alerts, in addition to or inlieu of, visual indicators provided on user interface 360. These one ormore auditory alerts are designed to provide an alert to a clinicaluser, such as when vapor delivery is complete, when liquid chamber mustbe refilled or the like. As will be recognized by those in the art,other components, while not shown, can be incorporated including any ofthe following: a keyboard; a real-time imaging system display (such as aCT, fluoroscopy, ultrasound); memory system; and/or one or morerecording systems.

FIG. 6 illustrates yet another aspect of the invention, in particular avapor catheter 200 embodying various features of the present invention.Generally, catheter 200 is adapted to operatively connect to aconnective handle of vapor generator 300 via hub assembly 202. Catheter200 includes elongate shaft 204 defined by proximal section 206 anddistal section 208. Elongated shaft 204 is formed with at least onelumen (such as a vapor, inflation, sensing, imaging, guidewire, vacuumlumen) extending from proximal section 206 to distal section 208 ofshaft 204. Starting at proximal section 206, catheter 200 comprisesstrain relief member 201.

Elongated shaft 204 further comprises at least one occlusive member 210disposed at distal section 208 and distal tip 210 having at least onedistal port 212. In one embodiment, the at least one distal port 212 isconfigured as a vapor outlet port. In yet another embodiment, vaporoutlet port may also be used as an aspiration port while catheter iscoupled to a vacuum source (not shown) in order to aspirate mucus,fluids, and other debris from an airway through which catheter 200 isadvanced prior to vapor delivery. Alternatively, catheter 200 can beconfigured to include a separate vacuum lumen and aspiration ports asneeded. Distal tip 210 can be adapted into a variety of shapes dependingon the specific clinical need and application. For example, distal tip210 can be adapted to be atraumatic in order to minimize airway damageduring delivery.

The dimensions of the catheter are determined largely by the size airwaylumen through which the catheter must pass in order to deliver thecatheter to an airway location appropriate for treatment of the one ormore target tissues. An airway location appropriate for treatment of atarget lung tissue depends on the volume of the target tissue and theproximity of catheter tip to the target tissue. Generally, catheter 200is low profile to facilitate placement of catheter distal tip 210 asclose as practicable to proximally and peripherally located target lungtissue, i.e. in order to facilitate the catheter's advancement intosmaller and deeper airways. In addition, the low profile feature ofcatheter 200 also ensures that catheter can be delivered to the lungsand airways through a working channel of a bronchoscope, including forexample, through the working channels of ultra-thin bronchoscopes.Preferably, catheter 200 is slideably advanced and retracted from abronchoscope working channel. The overall length and diameter ofcatheter 200 can be varied and adapted according to: the specificclinical application; size of the airway to be navigated; and/or thelocation of the one or more target tissues.

Occlusive member or members 210 are similarly configured to provide thesmallest possible size when deflated to facilitate ready retraction ofcatheter 200 back into the working channel of a bronchoscope followingcompletion of a treatment procedure involving delivery of one or morevapor doses to one or more target tissues. The one or more occlusivemembers 210 are provided to obstruct of proximal vapor flow and/or seatcatheter 200 in the patient's airway during vapor delivery withoutslipping.

Obstruction of an airway by occlusive member 210 prevents retrogradeflow of vapor to tissues located outside of the desired target tissues.Because of the physiological characteristics of the airways, inparticular the fact that the airways ventilate and communicate specificlung parenchyma or tissues, vapor delivered or dispersed at a particularairway location (e.g. at the bronchial, subsegmental, main bronchi)determines whether there is a focal or regional heating of tissue. Inaddition to location of the catheter distal tip, other considerationsthat impact whether there is focal or regional tissue heating patterns(i.e. volume of tissue heated or size of thermal lesion) createdinclude: time or duration of vapor delivery; the vapor flow rate; andvapor content (dry vs. wet; vapor alone vs. vapor cocktail). Preferably,the one or more occlusive members 210 are compliant to ensure: adequateseating; airway obstruction; and/or complete collapse followingdeflation.

Catheter 200 can be fabricated from a variety of suitable materials andformed by any process such as extrusion, co-extrusion, continuousextrusion, blow molding, or other methods well know in the art.Desirable qualities of catheter 200 include sufficient stiffnessfacilitating torque transfer and pushability balanced with flexibilityfacilitating tracking through tortuous airways; outer surface lubricityto facilitate passage of catheter 200 through a bronchoscope, guidecatheter, or the like; and a sidewall strength that prevents itskinking. In addition, catheter 200 and its various components arefabricated from durable enough materials for withstanding the hightemperatures and pressures of the vapor delivered through catheter 200.

Catheter 200 and elongated shaft 204 can be made of a variety ofmaterials including but not limited to: braided polyimide, silicone, orreinforced silicone. These materials are relatively flexible, yet havegood pushability characteristics, while able to withstand the hightemperature and pressure of vapor flow. In general, suitable materialsshould withstand or should be adapted to withstand vapor pressures of upto 100 psig, at temperatures up to 170° C. Examples of suitablematerials include various braided polyimide tubing available from IWHigh Performance Conductors, Inc. (Seewww.iwghpc.com/MedicalProducts/Tubing.html.) Similarly, the one or moreocclusive members 210 are preferably fabricated from similar materialshaving pressure and temperature tolerant attributes as elongated shaft204, but preferably which is also compliant, such as silicone availablefrom Dow Corning Q74720. As an added feature, catheter 200 and elongatedshaft 204 can further be adapted to include varying flexibility andstiffness characteristics along the length of shaft 204 based on theclinical requirements and desired advantages. While not shown, varioussensing members, including for example pressure, temperature and flowsensors known in the art can be incorporated into catheter 200. Forexample, catheter 200 can be adapted to include a sensing lumen foradvancement or connection with various sensory devices such as pressure,temperature and flow sensors.

Turning now to FIG. 7, illustrated is a preferred embodiment of a vaporcatheter 400. FIG. 7 is a longitudinal cross sectional view of theelongate shaft 404 while FIGS. 7A and 7B show transverse cross sectionalviews of the elongate shaft 404 taken along the lines 7A-7A and lines7B-7B respectively. In this preferred embodiment, catheter 400 comprisesan elongated catheter shaft 404 having an outer tubular member 406 andan inner tubular member 408 disposed within outer tubular member 406.

Inner tubular member 408 defines a vapor lumen 410 adapted to receive avapor and which is in fluid communication with a vapor flow circuit 314of generator 300. The coaxial relationship between outer tubular member406 and inner tubular member 408 defines annular inflation lumen 412.Vapor lumen 410 terminates at vapor port 424.

Inflation balloon 414 is disposed on a distal section of elongatedcatheter shaft 404 and having proximal 416 and distal 418 balloon endssealingly secured to outer tubular member 406. One or more inflationports 420 are disposed on outer tubular member 406 between the proximal416 and distal 418 ends of inflation balloon 414 so that the interior ofinflation balloon 414 is in fluid communication with inflation lumen412. (See FIG. 7B).

As shown in FIG. 7, structural members 422 are disposed between innertubular member 408 and outer tubular member 406 at distal vapor port 424to seal inflation lumen 412 and provide structural integrity at thecatheter tip. Structural members 422 are preferably made of stainlesssteel, nickel titanium alloys, gold, gold plated materials or otherradiopaque materials, to provide catheter tip visibility underfluoroscopy and/or provide sufficient echogenicity so that the cathetertip is detectable using ultrasonography. Hub assembly 426 (or otheradaptor) at the proximal end of catheter 400 is configured to direct aninflation fluid (such as a liquid or air) into inflation lumen 412 aswell as provide access to vapor lumen 410.

FIG. 7B illustrates inflation balloon 414 in an inflated or expandedconfiguration. Inflation balloon 414 inflates to a cylindrical crosssection equal to that of a target airway in order to obstruct the airwayand prevent proximal or retrograde vapor flow. This inflatedconfiguration is achieved at an inflation pressure within the workingpressure range of balloon 414. Inflation balloon 414 has a workinglength, which is sufficiently long to provide adequate seating in atarget airway without slippage during or prior to vapor delivery.

Provided are dimensions of suitable vapor catheters 400 in accordancewith the present invention. Outer tubular member 406 has an outerdiameter of about 0.05 to about 0.16 inches, usually about 0.065 inchesand an inner diameter of about 0.04 to about 0.15 inches, usually about0.059 inches. The wall thickness of outer tubular member 406 and innertubular member 408 can vary from about 0.001 to about 0.005 inches,typically about 0.003 inches. The inner tubular member 408 typically hasan outer diameter of about 0.04 to about 0.15 inches, usually about0.054 inches and an inner diameter of about 0.03 to about 0.14 inches,usually about 0.048 inches.

The overall working length of catheter 400 may range from about 55 toabout 150 cm, typically about 110 to about 120 cm. Preferably, inflationballoon 414 has a total length about 5 to about 20 mm; a working lengthof about 1 to about 18 mm, preferably about 4 to about 8 mm. Inflationballoon 414 has an inflated working outer diameter of about 4 to about20 mm, preferably about 4 to about 8 mm within a working pressure rangeof inflation balloon 414. In preferred embodiment, outer tubular member406 and inner tubular member 408 is braided polyimide tubular memberfrom IWG High Performance Conductors. Specifically, the braidedpolyimide tubular member comprises braided stainless steel, with thebraid comprising rectangular or round stainless steel wires, preferably,the braided stainless steel having about 90 picks per inch. Theindividual stainless steel strands may be coated with heat resistantpolyimide and then braided or otherwise formed into a tubular member orthe stainless steel wires or strands may be braided or otherwise formedinto a tubular product and the braided surfaces of the tubular productmay be coated with a heat resistant polyimide.

As will be appreciated by those skilled in the art, the devices,catheters and generators of the present invention can be used to heatone or more target lung tissue to treat a variety of lung diseases andconditions, including but not limited to lung tumors, solitary pulmonarynodules, lung abscesses, tuberculosis, other microorganisms, asthma aswell as a variety of other diseases and disorders.

In one embodiment, a procedure for inducing lung volume reduction (as atreatment for emphysema) involves advancing catheter 400 into asegmental or sub-segmental airway and delivering a controlled dose ofhigh temperature vapor. As will be appreciated by those skilled in theart, the vapor carries most of the energy and heat required to convertliquid in vapor generator from a liquid into a vapor. Upon dispersion ofthe vapor into the airways, the vapor penetrates into the interstitialchannels between the cells, and distributes thermal area over a volumeof tissue, permitting tissue heating to be accomplished quickly, usuallywith a few seconds or minutes. Vapor heating of target lung tissue isintended to cause tissue injury, shrinkage and/or ablation, in order tocause volumetric reduction of one or more target lung tissues. Lungvolume reduction is immediate and/or occurs over several weeks ormonths.

Depending on the extent of the volumetric reduction (complete or partialreduction of a lobe) desired, catheter 400 is navigated into one or moreairways, preferably into segmental or sub-segmental airways and thevapor is delivered into as many segmental or sub-segmental airways asneeded during a single treatment procedure to effect the therapeuticallyoptimal extent of lung volume reduction. In a preferred embodiment, avapor generator configured to create a vapor having a vapor pressurebetween about 5-100 psig, at a temperature between about 100-175° C.within vapor generator 300 is employed. The vapor catheter, having alength of about 55-150 cm in length and a vapor lumen inner diameter ofabout 0.03-0.14 inches is used to deliver into a sub-segmental airwaythat communicates with either the left and right upper lobes, and vapordelivered for a period of about 1-20 seconds during a single vapor shotinto one airway. Such a system configuration provides an energy deliveryrate of about 5 cal/sec to about 1500 cal/sec. Depending on the size anddensity of the lumen to be volumetrically reduced. The treatment can bemodulated, to effect volumetric reduction of a left or right upper lobe.Preferably, energy deliver to a target lung tissue is achieved withoutattendant plural heating sufficient to cause damage to the pleura or apneumothoraces.

As will be appreciated by one skilled in the art, various imagingtechniques (in addition to or in lieu of conventional bronchoscopicimaging) can be employed before, during and after a vapor treatmentprocedure. Real time fluoroscopy can be used to confirm depth ofcatheter 400 inside a patient's lung as well as confirm position ofcatheter in a desired airway. In yet another embodiment, real-time CTguided electromagnetic navigational systems, such as theSuperDimension®/Bronchus system can be employed to accurately guidecatheters of the present invention to the desired tissues targets,especially to get the catheters close to target tissues that areperipherally located. In one embodiment of the invention, the presentinvention can be adapted to work through a working channel of alocatable guide or guide catheter of the SuperDimension CT navigationalsystem.

A medical kit for vapor heating of one or more target lung tissuescomprises: a packaged, sterile liquid or liquid composition and a vapordelivery catheter. Other embodiments of said medical kits can compriseinstructions of use, syringes, and the like.

The invention has been discussed in terms of certain embodiments. One ofskill in the art, however, will recognize that various modifications maybe made without departing from the scope of the invention. For example,numerous variations, changes, and substitutions will now occur to thoseskilled in the art without departing from the invention. Moreover, whilecertain features may be shown or discussed in relation to a particularembodiment, such individual features may be used on the various otherembodiments of the invention. In addition, while not provided, otherenergy modalities can be employed for volumetric heating of target lungtissue and its understood that in conjunction with or instead of vapor,such as modalities such as RF, laser, microwave, cryogenic fluid, aresistive heating source, ultrasound and other energy deliverymechanisms can be employed for heating a target lung volume.

1. A patient lung volume reduction system comprising: a water vaporgenerator adapted to generate water vapor at a pressure of 5-100 psigfrom a location external to a patient; and a vapor delivery catheterhaving a proximal end adapted to communicate with the water vaporgenerator and a distal end adapted to be inserted through a workingchannel of a bronchoscope and placed within a lumen of the patient'slung.
 2. The system of claim 1 wherein the catheter further comprises avapor exit port and an occlusion balloon disposed proximal to the vaporexit port.
 3. The system of claim 2 wherein the catheter furthercomprises a balloon inflation lumen and a vapor delivery lumen.
 4. Thesystem of claim 3 wherein the vapor delivery lumen is concentric withthe balloon inflation lumen.
 5. The system of claim 1 wherein the watervapor generator is further adapted to deliver water vapor at an energydelivery rate of 5-1500 cal/sec.
 6. The system of claim 1 furthercomprising a vapor supply line communicating with the vapor generatorand the catheter, a priming circuit communicating with the vapor supplyline and a flow controller adapted to direct water vapor from the vaporsupply line into the priming circuit and into the catheter.
 7. Thesystem of claim 6 wherein the flow controller comprises a control valve.8. The system of claim 6 wherein the priming circuit comprises a vaporcollection unit.
 9. A patient lung volume reduction system comprising: awater vapor generator adapted to generate and deliver water vapor at anenergy delivery rate of 5-1500 cal/sec from a location external to apatient; and a vapor delivery catheter having a proximal end adapted tocommunicate with the water vapor generator and a distal end adapted tobe placed within a lumen of the patient's lung.
 10. The system of claim9 wherein the distal end of catheter is adapted to be placed within thelumen through a working channel of a bronchoscope.
 11. The system ofclaim 9 wherein the catheter further comprises a vapor exit port and anocclusion balloon disposed proximal to the vapor exit port.
 12. Thesystem of claim 11 wherein the catheter further comprises a ballooninflation lumen and a vapor delivery lumen.
 13. The system of claim 12wherein the vapor delivery lumen is concentric with the ballooninflation lumen.
 14. The system of claim 9 further comprising a vaporsupply line communicating with the vapor generator and the catheter, apriming circuit communicating with the vapor supply line and a flowcontroller adapted to direct water vapor from the vapor supply line intothe priming circuit and into the catheter.
 15. The system of claim 14wherein the flow controller comprises a control valve.
 16. The system ofclaim 14 wherein the priming circuit comprises a vapor collection unit.17. A patient lung volume reduction system comprising: a water vaporgenerator adapted to generate from a location external to a patient; avapor supply line communicating with the vapor generator; a primingcircuit communicating with the vapor supply line; a vapor deliverycatheter having a proximal end adapted to communicate with the vaporsupply line and a distal end adapted to be placed within a lumen of thepatient's lung; and a flow controller adapted to direct water vapor fromthe vapor supply line into the priming circuit and into the catheter.18. The system of claim 17 wherein the flow controller comprises acontrol valve.
 19. The system of claim 17 wherein the priming circuitcomprises a vapor collection unit.